1. Field of the Invention
This invention relates to a continuous process for the production of a CO-rich gas stream by the partial oxidation of a solid carbonaceous fuel. More specifically, the present invention relates to the production of synthesis gas by noncatalytic partial oxidation starting with gaseous CO.sub.2 -solid carbonaceous fuel e.g. ground coal, and a free-oxygen containing gas e.g. air, or substantially pure oxygen.
2. Description of the Prior Art
Oil embargoes coupled with already developing petroleum shortages have led to an energy crisis in this country. To help meet the accelerating demand for energy, exploration and development of conventional petroleum resources have been stepped up. However, long-term solutions demand that alternate energy resources be developed and utilized to the maximum degree. Coal is the most promising raw material in the USA for the production of synthetic natural gas (SNG) and synthesis gas i.e. mixtures of CO+H.sub.2. In the U.S. in 1970 the estimated recoverable coal reserves assuming 50 percent recovery were about 778 billion short tons. In comparison in the U.S. in 1974 the proved reserves of crude oil amounted to about 35 billion barrels.
H.sub.2 O is commonly used as a temperature moderator in the partial oxidation of hydrocarbonaceous fuels to produce synthesis gas. However, problems with water as a temperature moderator are encountered with solid carbonaceous fuels when water soluble solids separate and precipitate on heating surfaces in the system. Further, the high heat of vaporization of water reduces thermal efficiency. In coassigned U.S. Pat. No. 3.705,108 in addition to H.sub.2 O, inert gases such as nitrogen and CO.sub.2 were suggested to control the combustion of oil.
A principal limitation to the use of large reserves of sulfur-containing coal possessed by the United States in particular as well as some other countries is concern for environmental pollution. The subject gasification process appears to be a most feasible way of utilizing sulfur-containing coal for a wide variety of purposes, including the production of synthesis gas, fuel gas and the generation of power, with minimal or negligible deleterious effect upon the environment. Further, when production of synthesis gas i.e. H.sub.2 +CO and the processing of the synthesis gas by catalytic synthesis into oxygen containing hydrocarbons e.g. alcohols, aldehydes and into gasoline and diesel fuels, are both done at the mine, then cross-country rail transport of bulk coal may be eliminated at substantial savings. Advantageously, this may be done by the subject invention.